FabFilter

I am having trouble with my recent purchase of Fabfilter Pro-C 2. After having set up a compression, and got it working, and then re-opening the project later, I open the Fabfilter Pro-C 2 window and it is empty. The black area at the top is all that is visible, with three lines of controls: the track number and title, the line with the power button on the left, and the line with the Sidechain source. Everything else in the window is missing!

I have tried everything I can think of: closing and reopening the window, moving other windows on top trying to force it to refresh, etc, but I think this is more than a screen refresh issue. I think the plug-in may be malfunctioning. I say because my project music is not playing properly when I leave the plug in on. When I click the power button to turn it off, the music plays as expected. When I try to close the window, the DAW freezes up.

I am using Mixcraft. I have tried both the final version of Mixcraft 9 Pro Studio, and the new 10.1 release of Mixcraft 10, and the same problem seems to be there on both. I am really discouraged as I just learned how to use the product, and I finally understand compression, thanks to your tutorials and excellent product.

I hope you have some idea what is causing this. I checked the downloads, and I do seem to have the latest version, ffproc217x64. I purchased the product just two months ago, on July 24th.

Finally, this seems to only occur when I am using the sidechain feature. This may be a coincidence as I am adding sidechain compression to some products I am working on now.

Thank you for any help you can provide with this problem.